Ships Navigation Aircraft Inertial Alignment System (SNAIAS) is used on CV/CVA class aircraft carriers to furnish navigation data, as required, to establish the initial operating conditions of the Aircraft Inertial Navigation Systems (AINS) located on board an aircraft preparing for a mission.
The SNAIAS consists of two major subsystems, the Naviation Subsystem (NS) and the Aircraft Inertial Alignment Subsystem (AIAS). The NS generates required navigational data. The AIAS transmits analog data to the AINS aircraft via umbilical cables and alignment outlet boxes (AOB) in the hanger and flight decks. SNAIAS digital data is transmitted via a digital data radio link or AOB's via umbilical cables to the Aircraft Inertial Navigation System (AINS) in the aircraft and to Special Support Equipment via a connection box.
Older systems transmitted the required data by synchro signals. When newer systems added the capability on distributing this data via a digital link (both hardwired and RF), a hole developed in the Navy's capability to test the availability and adequacy of the data provided. A SNAIAS Digital Data Test Set was developed to fill this gap.